I've worked with MACs, PCs and Unix based office systems. In my experience, MACs truely are more user friendly than any of the other systems. Less of a learning curve.

I also found MACs less prone to problems and software glitches, BUT, when they did occur, they were impossible for the user to fix and the MAC consultant had to be called in. PCs overall probably had more problems, but were overall easier to fix and tinker with. PCs also had more unique scientific/engineering type software available than the MAC.

If you are starting from scratch and not doing anything exotic that requires some specialized scientific software, I would recommend the MAC due to the shorter learning curve for the user. If you have a history with PCs and know your way around a bit, I would go with a PC. I found trying to know 2 systems confusing; I kept hitting the wrong keys and getting confused.